Liquid controlled gyrocompass



June 23, 1931 P. E. HARRIS ,811,415

LIQUID CONTROLLED GYROCOMPASS Filed Aug. 29. 1929 INVENTOR fgfigy 5 09/6.

' ATTORNE Patented June 23, 1931 UNITED STATES PATENT OFFICE PERCY E. HARRIS, OF BROOKLYN, NEW YORK, ASSIGNOR TO BPERRY GYROSCOPE COM- PANY, 1110., OF BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK LIQUID CONTROLLED GYIROCOIMPASS- Application filed August 29, 1929. Serial No. 389,146.

This invention relates to gyroscopic compasses of the liquid controlled type and more especially to the prevention of the interrardinal rolling error in such type of compasses. Prior to my invention it had been the custom in practice in compasses employing two pairs of interconnected liquid containers, to run the connecting pipes directly from the north-east box to the south-east box and from the north-west box to the south-west box, such pipes having a substantial horizontal length in the north-south direction (see Patent 1,679,438, dated Aug. 7, 1928). Such compasses perform quite satisfactoril under normal conditions, but when teste on what is known as the high angle scorsby, which subjects the compass to a roll of substantially 45 on the side in a period of 8 seconds, such compasses show a tendency to wander slightl off the meridian. After a series of tests I ave discovered that by a novel arrangement of connecting pipes between the several containers I can prevent even this slight error and obtain more accurate results than ever secured before under such severe rolling conditions.

Referring to the drawings in which several preferred forms of the invention are shown;

Fig. 1 is a north elevation, partly in section, of a gyroscopic compass having my in vention applied thereto.

Fig. 2 is a diagrammatic view in plan of the liquid containers and their connecting pipes.

Fig. 3 is a similar view of a modified form of the invention.

Fig. 4 is a side elevation of the form of connecting pipes shown in Fig. 3.

The usual parts of a standard liquid controlled gyroscopic compass may be recognized in Fig. 1 wherein 1 is the gyro casing, 2 the vertical ring, 3 the follow-up element or ring and 4 the gravitational element pivoted on the follow up frame and connected to the gyroscope through the eccentric arm 5. On said frame 4 are mounted interconnected liquid containers 66 and 77, the containers 66 being to the north and south respectively of the vertical lane of the gyro wheel but positioned as s hown to the east of the gyro axis, while the boxes 77 are similarly positioned to the west of the gyro spinning axis. As stated above, the prior practice had been to directly connect boxes 66 and 7-7. According to the form of the invention shown in Figs. 1 and 2, however, I run one pipe 9 from box 6 down-underneath the compass and diagonally across to the box 7 and similarly run the pipe 10 down from the box 7 underneath the compass and diagonally across to the box 6. By such arrangement the horizontal portion of each tube, which is in line with the acceleration forces due to the rolling, is largely reduced, the pipes being curved so that a large portion of their length extends in a vertical rather than a horizontal plane.

In addition, it should be noted that when the ship is rolling in intercardinal planes there are no lateral acceleration forces acting on one of the tubes, namely, the tube at right angles to the plane of roll, so that for a NE-SW roll (for instance) there will be no tendency to cause any flow between the boxes 6 and 7. While there would probably be a somewhat greater tendency to cause a fiow under such circumstances between the boxes 7 and 6', double the flow would not occur because although the acceleration force would be greater the flow is not directly proportional to the force tending to cause the same. It should also be noted that any transfer. of the mercury in the E-W direction does not affect the operation of the compass.

Still a better form of my invention is shown in Figs. 3 and 4. In this form the boxes 16 and 17 are connected by a tube 11 and boxes 16 and 17' by a tube 12, which tubes run east and west. This is a new principle of roscopic compass design in which hereto ore containers have only been connected in the north-south direction. This secures more uniform performance, regardless of the plane of roll of the ship. Then, in addition, the tubes 11 and 12 are cross connected by a single downwardly looped wardly ing and pitching.

pipe-13. The tubes 11 and 12 are also downlooped to some extent as shown in Fig. 4. This form of the invention seems to possess most of the advantages of the form shown in Figs. 1 and 2. n add1t1on,' 1t providesa path oi flow of the mercury with tends'very strongly to prevent surging on the quick acceleration pressures due to roll- As is well known in the art, the most serious rolling action is in the intercardinal planes and when such occurs in this form of the invention in the northeast south-west directions, for instance, the predominating tendency would be to cause a flow from the box 16 to 17 and from 16' to 17' owing to the greater length of pipe in the E-W direction. The lesser tendency of the mercury to flow in the N-S direction is thus largely overcome. Looked. at in a different way, the mercury in flowing from the box 16 into tube 13 would tend to drag some of the mercur out of the box 17 the flow being resiste thereby. In addition, the mercury flowin from the tube 13 into the tube 11 towarcf box 17 would tend to drag some of the mercury out of box 16 thus again retarding the flow, and whatever displacement of the mercury might take place in the boxes 16 and 17 or 16 and 17 would not affect the compass as said boxes lie on opposite sides of the N-S axis. The flow of the mercury around the bends in the pipes also tends to reduce the surge.

An advantage of the form shown in Figs. 3 and 4 over that shown in Fig. 2 is that the intercardinal acceleration force acts through an angle of on the mercury in pipe 1350 that it does not receive as great a disturbing force as the mercury in pipe 10, for instance, in 2. On the other hand there is only one pipe 13 used in Figs. 3 and 4 while in the old form of the compass employing the two pairs of boxes there was a pipe directly connecting boxes 16-16 and 17-17'. f

It should further be noted that the advantages of the form of the invention shown in Figs. 3 and 4 may largely be secured in the form shown in Fig. 1 simply by tapping botlf pipes 9 and 10 near their mid point and soldering together so that the two pipes are interiorly connected.

In accordance with the provisions of the patent statutes. I have herein described the principle and operation of my invention, together with the'apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means. Also, while it is designed to use the various features and elements in the combination and relations described, some of these may be altered and others omitted without'interfering with the more general results outlined, and the invention extend! to such Havin described my invention, what I claim an desire to secure to Letters Patent is-: I

i 1. In a liquid controlled gyro-compass, the combination with gyroscoplc element, a pluralitv ofli. uid containers-located on the north side t ereof and s seed in the E-W direction, a plurality 0 liquid containers located on the south side thereof and similarly spaced, and means interconnectin said containers in both the E-W and N-S ections.

2. In a 1i uid controlled ro-compass,

the combination with gyrosco 1c element, a

plurality of liquid containers ocated on the north side thereof and spaced in the E-W direction, a pluralit of liquid containers located on the south side thereof and similarly spaced, and means connecting diagonally opposite containers.

3. In a liquid controlled gyro-compass, the combinatlon with gyroscop1c element, a plurality of liquid containers located on the north side thereof and spaced in the E-W direction, a plurality of liquid containers located on the south side thereof and similarly spaced, a pair of' pipes connecting the con tainers in the E-W direction and means interconnecting said pipes to permit flow of liquid in the N-S direction.

4. In a liquid controlled ro-compass, the combination with gyroscopic element, a plurality of liquid containers located on the north slde thereof and spaced in the E-V direction, a plurality of liquid containers located on the south side thereof and similarly spaced and downwardly looped pipes interconnecting all containers.

5. In a liquid controlled gyro-compass, the combination with gyroscopic element, a plurality of liquid containers located on the' cated on the south side thereof and similarly.

spaced, said containers being further apart in the E-W direction than in the N-S direction, and a pair of pipes connecting the containers in the E-W direction and means interconnecting said pipes to permit flow of liquid in the N-S direction.

6. In a liquid controlled gyro-compass, the combination with gyroscopic element, a plurality of liquid containers located on the north side thereof and spaced in the E-W direction, a plurality of liquid containers located on the south side thereof and similarly spaced, a. pair of downwardly looped pipes connecting the containers in the E-W direction and a downwardly looped pipe in terconnecting said pipes to permit flow of liquid in the N-S direction.

In testimony whereof Iaifix my signature.

PERCY E. HARRIS. 

